Adjustable and reversible propeller



June 30, 1925. R 16,102

s; HEATH ADJUSTABLE AND REVERSIBLE PROPELLER Original Filed Dec. 4. 1919 5 Sheets-Sheet 1 I E 3 a Q Jime 30, 1925.-

' s. HEATH ADJUSTABLE AND REVERSIBLE PROPELLER 5 Sheets-Sheet 2 Original Filed Dec. 4. 1919 gnpgnkoo June 30, 1925. R 16,102 s. HEATH ADJUSTABLE AND REVERSIBLE PROFELLER Original Filed Dec. 4, 1919 5 Sheets-Sheet 5 June 30, 1925. R 16,102

I s. HEATH v ADJUSTABLE AND REVERSIBLE FROPELLER Original Filed Dec. 4, 1919 5 Sheets-Sheet 4 affnzucq June 30, 1925.

s. HEATH v ADJUSTABLE-AND REVERSIBLE PROPELLER Original Filed Dec. 4, 1919 5 Sheets-Sheet 5 June so, 1925.

UNI-TED STATES Re-l6,l02

PATENT OFFICE.

. SPENCER, HEATH, OF BALTIMQBE, IARYLAN'D.

ADJ'USLLBLE AND QEY'ERSIBLE ZBOPELLEB.

Original ll'o. 1,447,080, dated I'ebruary 27, 1923, Serial- No. 342,379, filed December 4, 1919. Application for reissue filed February 26, 1925. Serial No. 11,898.

To all whom it may co cern.

' Be it known that I, SPENCER HEATH, a citizen of the United States, residing at Baltimore, State of Maryland, have invented cer- 5 tain new and useful Im rovements in Adjustahle and Reversible ropellers, of which the following is a specification. v Thisinvention relates to screwpropellers, more particularly to propellers for aircraft, and to that type or class of propellers in which the blades are capable of simultaneous adjustment about their several longi tudinal axes in such manner that the pitch of the blades can be varied at will or the action of the blades entirely reversed to any desired degree, all durin continuous operation of the propeller either at rest or in flight. The present invention is of a similar nature to that covered by my'copending application Serial No. 308,112, filed July 2, 19l9,and its objects are generally the same. -Among the features which it comprises, in common with such prior invention are, that the blades are adjusted by engine power delivered 'to the propeller, manual or bodily force being required only for connecting and disconnecting the operating power; and that there are no operative connections, such as clutch collars, running hearings, or the like, normally in engagement, such connections being established only momentarily during changes in adjustment of the blades.

While the apparatus of my said prio'r in vention is satisfactory for small or medium sized propellers, it has' been found. somewhat heavy for the larger sizes. A specific object of the prwent invention, therefore, is to provide a lighter and more compact construction. To this end, I have devised new and sim lified operating mechanism, such mec anism including a smaller number of gears, and an improved duplex worm drive for adjusting the blades, and securely locking them in an y position.

A further object of this invention is to provide a new and improved bearing mechanism to permit rotation of the blades, this mechanism being of the turntable typeto avoid the use of lo sleeves or sockets for reception of the bla d es, and thus reduce the weight of the I .Another. 0 'ect is to provide a means and -method to secure attachment between the several blades, and their sockets or ferrules which engage the bearing mechanism.

With thev foregoing and other objects in view'I have invented the improved mechanism more particularly described hereinafter, and illustrated by means of the accompanying drawings, which-are a part of this specification, and in which;

Fig. 1 is a longitudinal section coinci ding; with the axes of bothblades and the S a I w l i Fig.2 is a section on line 2-2 of Fig. 1, part of the gear casing being broken away.

Fig. 3 is an end. view of Figs. 1 and 2 sgoFwn partly in s'ectionthrough line 33 0 1 4 is a'fragmentary side view of Figs. 2 and 3, the gear casing being in section.

Fig. 5 is a plan view of brake housing and controllever. I

Fig. 6 is a section on line 6-6 of Fig. 5. Fig. 7 is a section on line 7-7 of Fig. 5. Fig.8 is a longitudinal section through a .ferruleiand' blade shank as hitherto made.

Fig.'9 is anend view-of Fig. 8.

Fig. 10 is a longitudinal section through a ferrule and blade shank'in accordance with the present invention.

Fig. '11 is anend view of Fig. 10.

Fig. 12 is .a side view of the operating lever detached.

' The parts are designated by corresponding numerals throughout the several views.

Referring to the. drawings:

1 is the power delivery shaft on and with which the propeller as a whole revolves, and

which is secured in the tapered bore of the propeller hub 2 by means of the diflerential nut 3 whichis sufiiciently extended in length to protrude slightly beyond the end of hub 2 -at which protruding end the nut is provided with holes 4 for reception of a bar to turn the nut.

The hub is rovided with a cylindrical portion one-hali 5 of which is keyed or welded securely to the hub and the other half 6 of which is removably mounted on the outler 3,151 0; the hub afid to all:

art 5 ts en an on pa a-nd 6. The 5 and 6 are sf) shaped as to form a. shallow socket for the reception of th i'nner ends of the blades as hereinafter .d 'ribed.

The exterior .Q the cylindrical portion formed by the union of parts and 6 is of even contour except for the bolt flan es 8; its interior, however, is provided wit circular flanges 9 and 12 for rece tion of ball races and 13 carrying the caring balls 11 and 14.

- The blades of the propeller are illustrated two in number but a greater number of blades may be used by the addition of similar corresponding arts. The blades are referably of wood, ut other materials may Be used. The shanks of the blades are secured in ferrules 21, which are of double tapered form, with a constricted central portion 25, as shown in Fig. 1. The shanks are forced into the ferrules under heavy pressure and'the ends of the blade shanks are then expanded to fill up the flaring inner ends of the ferrules. Hitherto the'expanding of the shanks has been accomp ished solely by means of wedges. It has been the practice to make the ends of the shanks:

cylindrical in form and but little, if any, larger than the smallest portion of the ferrule, as indicated by dotted lines in Fig. 8, and to use a ring wedge 22 concentric with the'ferrule to expand the shank. This expansion, by increasing the circumference of the shank, caused radlal openings into which were inserted wedges 23. The expansion of the shank by ring wedge 22 caused an outward bending of the wood, with consequent rupture or stres of its fibres at and beyond the toe of the wedge in the small portion of the ferrule, as shown at A in Fig. 8. 4

In order to avoid this difliculty, I have devised an improved method of securing the shanks in the ferrules.

In my improved method, the shank is first prepared with a double tapered form corres nding with the interior of the ferrule.

t the entrance to the ferrule, at'24, (see Figs. 8 to 11) the shank is made but slightly larger than the interior of the ferrule. At the throat or smallest diameter of the ferruleas at 25, the shank is made one-quarter to one-half inch lar er in diameter than the interior of the ferrlfie. At the inner end of the ferrule the butt of the shank is made equal or nearly equal in diameter to the inside of the ferrule. The contour of the blade shank before it is inserted in the ferrule is indicated by the dotted lines 28 in compressing the wood.

Fig. 10. In order to insert the shank it is necessary to reduce its end diameters to that of the restricted portion of the ferrule by This is accomplished without injury to the parts by coatlng the shank and ferrule with lead pigment and varnish and imparting a slow rotary motion to the shank while being ressed into the ferrule. By thisrotary motion between the parts it is possible to cause a cat compression of the wood without requiring very'heavy or injurious end pressure to in-.

,sert the shank. After being inserted, the .compressed end of the shank slowly expands I to fill u the flaring inner end of the ferrule. T is expansion may be hastened or completed by the applicationof moisture. The circular wed e 22 is now inserted in the butt of the shan for the purpose of compressing the wood against the inner' walls of the ferrule. This is accomplished without causing radial openings in the wood and without undue bending or rupture of the fibres at the toe of' the circular wedge, for the reason that there is practically no bendin due to the wedge. In practice I find it ad vantageous to insert additional wedges 26, preferably in a radial arrangement both outside and inside of the circular wedge, as shown by Fig. 11, for the purpose of further compressing the wood in the butt end of the shank.

To facilitate insertion of the wood shank the inner walls of the ferrule are made for the most part smooth. This smooth'ness extends from the entrance end 24 for a distance slightly beyond the throat 25 from which plomt the inner surface is made rough or slig tly serrated or corrugated as indieated at 27 in Fig. 1-0. This is for the pur- .pose of increasing the security of engagement between the shank and ferrule.

The inner end of ferrule 21 for each blade is provided with a flange 30. On one side of this flange is seated a ball race 31' to coact with race 10 while the other side carries a ferrule is provided with worm-gear teeth 31' to engage the worms 32 mounted on the exterior of the hub eccentrically of the shaft 1 and engaging through the apertures 33.

Worms 32 are driven through shafts 34 by worm gears 35 which in turn are driven by worms 36 each of which is integral with its pinion gear 37.

The portion of the hub 2 containing the taper bore for the shaft has an inner extension 39 upon which is journaled a sleeve 40 carrying on one end a brake wheel 41 and on its other end the spur gear 42. The sleeve 40 is held in position on the hub by means of the nut 15' threaded on the extension 39' of hub 2. Between brake wheel 41 and spur gear 42 the sleeve 40 carries, journaled upon it, a second brake-wheel 43 carrying upon its hub extension 44 a spur gear 45- adjacent to and somewhat larger than s ar 42 on sleeve 40. Gear 45 meshes irect y into the two pinions 37, Gear 42 meshes into a cylindrical portion 5 of the pair of idlers which idler in turn mesh with pinions 37. It is thus seen that relative rotary motion between either brake wheel "and the propeller hub would communicate motion to pinions 37, and pinions '37 would in, turn communicate a reverse motion-to the other brake wheel. From this it becomes clear that, for a given direction of relative turning of the brake wheels, either forward or reverse motion of pinions 37 may be obtained according as one or other of the brakewheels is turned in the given direction, and pinions 37 communicate this optional motion through worms 36, worm mechanism is between the plane of the axes of the blades and the source of power for "the shaft 1, regardless of whether the propeller is of the pulling or pushing type.

For convenience in mounting the idlers 46, pinions 37 and their associated worms and gears, I provide an assembly ring 38 fitting cylindrical portion 5. This assembly ring carries two, long bosses 34 to provide journal l)earings ..or shafts 34: also two bosses 47 for support of studs 47 on which are journaled p1'nions37, and also two bosses 48 to support-the idler studs 48. The asembly ring is secured firmly in position by the studs 47 and 48 being extended through their homes on the ring and screwed firmly into the body of the hub below. As a furtherse'curity,"the opposite ends of the studs are held in position by the casing and gear housing "49 which is provided with holes to receive the ends of the studs and support them as shown in Figs. 3 and 4. The housing 49 is flanged where it attaches to'the hub and is secured thereto by screws 49'.

I will now describe my meansof producingrelative motion between either of the two brake wheels 41 and 43 and the pro peller hub.

The crank case 50 (or other fixed strucmm from which the shaft 1 protrudes) has secured to itby brackets 50 the brake band housing 51 which provides two annular recesses for leather lined brake bands 52 and 53. Each band 52 and 53 is secured at one end to the housing 51 as shown at 55 in Fig. 6, from which point they lie closely around in their recesses in circular form with their free ends protruding from the housing through apertures 56 and 57. On the periphery of the housing and between .secured to lugs- 60 and 60 carried by the the apertures mentioned there is mounted 1 an operating lever 60 having alternative ful- I crums on pivots in pins or studs 61 and 62 which are firmly inserted in the lever and which rest at the bottom of double slots 63 and 64 formed in plates 65 an'd 66, and are, held there by the spring of bands 52 and- 53, whose freeends are connected with studs 61 and 62. The plates 65 and 66 are firmly housing '51, with suflicient s ace between them to receive the thickness 0 the lever 60. The .leveris operated from-its up r end by means of any suitable rod or mec anism engaging the-eye 67 (Fig. .12) and capable of trusting operator s will. When the lever is moved to the right the stud 61 remains in the bottom of slots 63 while stud 62 moves towards the top of slot 64 and thus tightens the brake band 52. Similarly, a movement of lever 60 to the left tightens brake band 53.

The position of the brake-housing 51 relative to the propeller shaft is such that when the propeller is mounted the brake wheels 41 and 43 will be in position to be engaged by the bands 53 and 52 respectively, whenever either of these bands shall be. contracted by operation of lever 60.

g The propeller being mounted and in closely around "the hub 2 and against the operation, the adjusting or'reversing of the the lever in either direction at the blades is accomplished bythrusting lever 60 1 momentarily in one direction or "the other, according to the effect desired. The gripping of one of the brake wheels causes rela-v tive motionbetween-it' and the revolving propeller, thus setting the various gears in motion and adjusting the blades.

3 Having thus described the invention, what is claimed as new and desired to be secured by Letters, Patent is:

' 1. A ropeller comprising a hub, a plurality o ferrules rotatably mounted therein, a blade secured in each ferrule.) and thrust bearings between each ferrule and the hub for resisting both inward and outward radial movement of the blades "relative to the hub, the major portion of each of said '3 ferrules lying radially beyond and substantially outsideof said hub. 2. A propeller comprising a hub, a plurality of ferrules 'rotatably mounted therein,

tegral annular flange carried by each ferrule adjaeentits inner end, and anti-friction thrust bearings" on'both sides of said flange, between" the flange and hub.

rality of ferrules'rotatably mounted therein, u a

a blade secured in eachferrule, a radial inblade meshingwith said gear,

' so rotating said blades,

4. A ropeller comprising a hub, a pluferrules rotatably mounted thererality o in, a blade securedin each ferrule, a radial annular flange carried by each ferrule, gear teeth formed on the periphery of said flange, and means engaging saidteeth for rotating the blades on their axes.

5. A propeller comprising a hub, a plurality of ferrules rotatably mounted therein, a blade secured ineach ferrule, a complete gear wheel carried by each ferrule, and a second gear engaging each of said wheels for rotating last named gears being arranged rearwardly of the axes of said blades. 6. An aircraft propeller comprising a shaft, a hub mounted thereon, a plurality of ferrules rotatably mounted in said hub, a blade secured in each ferrule, a worm wheel carried by each ferrule, a worm engaging each worm wheel, said worms being arranged eccentrically of said shaft and rearwardly of the axes of said blades, and means for rotating said worms to adjust the blades on their axes.

7, A propeller comprising a hub, a plurality of'blades mounted therein so as to be capable of rotation on their own axes, and means for so rotating said blades, such means comprising two separate sets of worms and worm wheels for each blade, arranged in series.

8. A propeller comprising a hub, a pluralit of blades mounted therein so as to be capa le of rotation on their own axes, and means for so rotating said blades, such means comprising agear, a pinion for each and gearing comprising two sets. of worms and worm wheels between each pinion and its corresponding blade.

9. A propeller comprising a hub, a shaft to which the hub is secured, a plurality of blades mounted therein soas to be capable of rotation on their own axes, and means for such means comrising a gear'concentric with and surrounding said shaft, for each blade, meshing with said gear, and gearing comprising a worm and worm wheel between each pinion and its corresponding blade.

10. A propeller comprising a hub, a plurality of blades, carried thereby, and mounted for rotation on their own axes, and means for so rotating said blades in either direction, such means comprising a pair of gears concentric with the hub, a; palr'of pinions for each blade meshing respectively with said gears and with each other, and means for transmitting the movement of one of said pinions to the blade.

11. A ropeller comprisin a hub, a plurality of lades carried there y, and mounted for rotation on their own axes, and means the blades on their axes, said' the constricted portion of a plurality of pinions, one

for so rotating said blades ineither direc tlon, such means comprising a pair of gears concentric with the hub, gearing connecting portion, which consists in making the shank of double tapered form similar to the .ferrule, and having an enlarged end, compressing such enlarged end and forcing it through the constricted portion of the ferrule, and then expanding such end to fill the tapered portion of, the ferrule.

13. The hereindescribed method of securing a wooden blade shank in a double ta-, pered ferrule having a. constricted middle portion, which consists in making the shank of double tapered form similar to the forrule, but with its smallest diameter larger than the constricted portion of the ferrule, and having an enlarged end, compressing such enlarged end and forcing it through the ferrule, while compressing the smallest part of the shank to fit such constricted portion, and then expandingsaid enlarged end of theishank to fill the tapered portion of the ferrule.-

14. In a propeller ,a double-tapered ferrule having a constricted portion, and a blade having a double tapered shank substantially filling said ferrule, with the material of the shank compressed where it lies within the constricted portion of the ferrule.

15. In a propeller construction, a shaft, a propeller hub mounted thereon, a plurality of ferrules rotatably mounted in said hub, a blade secured in each ferrule, a radial annular flange carried by each ferrule, gear teeth on said flange, and means for engaging said teeth and rotating said ferrules and blades, said means being arranged wholly externally of said shaft.

16. A propeller construction comprising a hub having a plurality of shallow sockets. a ferrule rotatably mounted in each of said sockets, a blade secured in. each ferrule, a radial annular flange carried by each ferrule substantially at its inner end, said hub haging two spaced integrally connected flanges surrounding each tween which said ranged and first named hub.

17 A propeller construction comprising a shaft,-a hub, a plurality of ferrules rotatably mounted on said hub, a blade sefirst named flange is arthrust bearings between said flange and the flanges -on said The hereindescribed method of securof said sockets and becurediin each ferrule, a gear wheel by each ferr' 1e, and gear mechanism for retating said gear wheels, said gear mechanism being arranged rearwardly of the axes of said blades and externally of said shaft.

18'. A propeller comprising a hub, a plurality of blades mounted thereon so as to becapableof rotation on their own axes, and

means'for so rotating saidblade, said means comprising two-separate'sets of worms and worm wheels for each blade arranged in series, means for causing simultaneous rotation of each of said sets of worms and worm wheels in one direction, and other means for causing simultaneous rotation of each of said sets or worms wheels in the o posite direction.

19. A propelicr comprising a hub having a socket, a blade having a shank rotatable about its own axis in said socket, and means and worm for so'rotating said blade shank in either direction, said means comprising a pair of 1 independent toothed gears journaled on said hub, a gear wheel ineshing with one of said gears, and an idler pinion meshing with said gear wheel and the other of said gears.

20. The combination with a propeller having angularly adjustable blades,-and means associated with each 'blade for angular] adjusting the same, of a pair of brake whee normally rotating with the propeller, and

' operatively connected through reverse gearmg with said adjusting means, a pair of brake bands for said wheels, a controllin lever to which one .end of each brake-bang is secured, and a pair of spaced pivots about which said lever is mountedto s for respectively tightening said .brakeban 21. The combination with a propeller hav ing angularly adjustable blades, and means associated with each blade for angular-l adjustin the same, of a pair of brake w eels norma y rotating with the propeller, andoperatively connected through reverse gearing with said adjustin brake bands forsaid w eels, a contro means, a pair of lever to which one end of each brakeban ,is secured at separated points, and a pair of spaced 'ivot ins'about which said lever is moun to se ectively swings-for tightening said respective brake ban 22. The combination with a propeller having angularly adjustable blades, and means associated with each blade forangularligdjustingthe same-of a pair ofbrake w' ls worm rigidly lever at separated points, about ei er of which ivotpinsthe lever may swing, and one en of said brake bands being secured respectively to said pivot ins.-

23. The combination wi a propeller having angularly'adjustable' blades, and means associated wlth each blade for angularly adjustin thesame, of a pair of brake wheels norma 1y rotating with the propeller, and operatively connected through reverse gear-' ing with said'adjust' means, a pair of brake bands for said fiieels, a controlling lever, guide plates between which said lever is free y mounted, a .pair of spaced pivot pins carried by saidv lever, said guide plates having curved slots through which said pins freely work, each slot being formed on an arc of a circle of which the o posite in is the center, and one end of sai brake ands being secured to said 'lever at separated points, said lever. being adapted. to swing about either one pin or the other to selecwheels and hands, a crank case brackets se-' cured to said crank case and wpportins said he and a controlling lever'mounted on said. ousing and connected with the brghmkanda' ll h b h -prope er compns a u avmg .a socket, a blade a ank rotatable about its own axis in and socket, and-means for so rotatinlg said blade shank in either direction, sai means comprising a ir of inde ndent toothed gears journal] on said hu coaxially thereof,'a gear wheel and connected and rotatably supported on said hub, said worm o tively connected with said blade shank, said gear wheel being in mesh. with one, of said toothed ars, and an idler pinion meshing with saifiast mentioned other of said toothed gears.

In testimony whereof I hereunto afix my signature.

SPENCER HEATH.

108 gear wheel and v 

